Male bustards' success is measured by their 'beards'

Washington, Feb 9 (ANI): For the first time, a study has shown that the 'beards' and the design of the neck are 'reliable' indicators of the weight and age of the great bustard (Otis tarda).

They are also used to both avoid fights with competitors and to attract females.

"The heaviest males (best physical condition) make it known to other males through the length and number of 'beards', and thereby avoid bloody fights to ascend in rank which would occur if these signals did not exist", said Juan Carlos Alonso, main author and researcher in the Spanish National Museum of Natural Sciences (CSIC) informs SINC.

The study has shown that great bustard males achieve greater reproductive success and avoid "dangerous" and "unnecessary" confrontations due to the extent of development of their plumage.

"Despite all this, sporadic fights do occur which lead to, on some occasions, the death of one of the contenders", said Alonso.

According to the scientist, when they are being chosen by the females, the oldest males "can compensate for a certain deficit in weight with greater experience thanks to their more advanced age".